Group 2

• Why does ionization energy decrease down the group?

  -each element down the group has an extra electron shell

  -Inner shells shield the outer electrons from attraction from the nucleus

  -Electrons are further away from the nucleus, which reduces the electrostatic attraction between the nucleus and the outer electrons

  this makes it easier to remove outer electrons so the ionization energy decreases

  this also means reactivity increases down the group
• Reaction of group 2 metals with water M + 2H2O —> M(OH)2 +H2
• Reaction of group 2 metals with oxygen 2M + O2 —> 2MO
• Reaction of group 2 metals with chlorides: M+ Cl2 —> MCL2
• Generally compounds of group to with a single charge ion increase in solubility down the group
• compounds of group 2 with a doubly charged ion decrease in solubility down the group
• group 2 hydroxides increase in solubility down the group
• group 2 sulfates decrease in solubility down the group
• Hydroxide ion?

  OH-
• Nitrate ion?

  NO3 -
• Sulfate ion?

  SO4 2-
• Carbonate ion?

  CO2 3-
• Hydrogencarbonate ion?

  HCO3 -